He called on the police to “take a firm stance” against protesters who were “significantly disrupting the lives of others”.

“Over recent days, commuters trying to earn a living have been unable to travel to work and businesses have been disrupted,” he said, following a meeting with Met police chiefs.

Scotland Yard defends response to climate change protests

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“Emergency vehicles have faced difficulties navigating the road networks and the demonstrations have put added pressure on police officers whose job it is to solve crimes and protect the public.

“Let me be clear: I totally condemn any protesters who are stepping outside the boundaries of the law. They have no right to cause misery for the millions of people who are trying to lead their daily lives. Unlawful behaviour will not be tolerated.”

Hundreds have been arrested and more than 1,000 officers deployed to police the protests, which entered their fourth day on Thursday.

They said demonstrators’ tactic of lying down meant four officers were needed to make an arrest but said there was no legal justification for more draconian tactics, such as kettling and mass-arresting groups, because the demonstrations were peaceful.

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4:05

'If this is what it takes': London​ reacts to the Extinction Rebellion ​'shutdown' – video

Politicians have struggled to respond to the protests, as they are keen to head off complaints that not enough is being done to tackle climate change at the same time as taking a tough stance against disruption to commuters.

Javid and Sadiq Khan, the mayor of London, have come under pressure from the rightwing press in recent days to take a more outspoken stance against any protesters disrupting public transport or acting illegally.

“The Met’s ability to police protests without impacting on core policing priorities – such as tackling knife crime – has been made significantly harder by the huge cuts to government police funding,” he said.

Citing £850m of cuts to the force since 2010, he added: “Whether to tackle violent crime, or police protests, our brave police officers deserve the resources they need to keep us safe.”

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He highlighted the increasing cost of policing a growing number of protests in London, and said he was working with the Met to consider claiming for a special grant to help with costs for the current demonstrations.

He has said on Twitter that the world is “facing a climate emergency” and that he “fully supports the right of protesters to protest on this vital issue”, while urging organisers to “work with police to ensure their demonstrations are peaceful and lawful and that disruption is kept to a minimum”.

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0:39

Climate protesters climb on top of train at Canary Wharf – video

The environment secretary, Michael Gove, said: “We’ve got the message,” after some activists glued themselves to a train and others chained themselves to a garden fence at the home of the Labour leader, Jeremy Corbyn.

Claire Perry, the energy and climate change minister, also said that she “got the science, motivation and passion driving climate emergency protests” but could not see that “disrupting one of world’s busiest transport systems … blocking emergency routes and making life difficult for so many is going to build consensus and support for the changes we need”.